MONTICELLO — Michelle LaFrance admitted Wednesday that she did nothing to stop her boyfriend Paul Novak when she learned he intended to make chloroform and kill his estranged wife, Catherine.

LaFrance told a Sullivan County jury under questioning by Novak's attorney, Gary Greenwald, that Paul told her of his plan "about a week" before Catherine's death on Dec. 13, 2008. He planned to make untraceable chloroform to knock her out and then burn down the Lava home to make it look like an accidental fire, she said.

"Did you tell him not to do it?" Greenwald asked.

"No, sir."

"Did you ever raise the issue, 'Please don't do this.'"

"Never."

"Did you say, 'Please stop it."

"No."

Novak, on trial in Sullivan County Court before Judge Frank LaBuda on first-degree murder charges, is accused of strangling Catherine in the basement when the chloroform concoction did not work.

LaFrance, one of two key witnesses against the former Queens paramedic, struggled to recall certain details of the night of Dec. 12, 2008, when she says she stood next to Novak in the attic while he was mixing the chemicals with a pitcher and a bowl of ice. Novak, she said, told her to look for "a swirl."

She said she and Novak drove to Sullivan that day and picked up Novak's two kids at Sullivan West, where Catherine worked. They stopped for dinner on the way home. When they got to their Long Island apartment, Paul played with the kids for a little while. LaFrance said she reminded Novak to give the kids Benadryl strips so they would sleep through the night while he was away carrying out the murder. Paul then went to the attic and began to mix chloroform.

"What time did Paul go upstairs?" Greenwald asked.

"I don't know."

LaFrance also couldn't recall what time Scott Sherwood — the prosecution's second key witness against Novak — arrived at the house, how he got into the house, or what he was wearing. Sherwood, who has already pleaded guilty in the case, showed up at about 11 p.m. LaFrance said Sherwood didn't know that Novak planned to kill Catherine and only discovered the plot while they were standing around in the attic.

She said Novak poured the substance into a bottle and walked out of the apartment carrying the pitcher and ice to Sherwood's SUV. He was worried that the chloroform could be traced and so he later threw away the pitcher and bowl.

"You are hours away from a homicide," Greenwald asked LaFrance. "What is going through your mind?"